Cortical and autonomic modulation of attentional control /

View/Open

Date

Author

Metadata

Abstract

Whereas the role of the anterior cingulate cortex (ACC) in cognitive control has
received considerable attention, much less work has been done on the role of the ACC in
autonomic regulation. Its connections through the vagus nerve to the sinoatrial node of the
heart are thought to exert modulatory control over cardiovascular arousal. Therefore, ACC is
not only responsible for the implementation of cognitive control, but also for the dynamic
regulation of cardiovascular activity that characterizes healthy heart rate and adaptive
behaviour. However, cognitive control and autonomic regulation are rarely examined
together. Moreover, those studies that have examined the role of phasic vagal cardiac control
in conjunction with cognitive performance have produced mixed results, finding relations for
specific age groups and types of tasks but not consistently. So, while autonomic regulatory
control appears to support effective cognitive performance under some conditions, it is not
presently clear just what factors contribute to these relations.
The goal of the present study was, therefore, to examine the relations between
autonomic arousal, neural responsivity, and cognitive performance in the context of a task
that required ACC support. Participants completed a primary inhibitory control task with a
working memory load embedded. Pre-test cardiovascular measures were obtained, and ontask
ERPs associated with response control (N2/P3) and error-related processes (ERN/Pe)
were analyzed.
Results indicated that response inhibition was unrelated to phasic vagal cardiac
control, as indexed by respiratory sinus arrhythmia (RSA). However, higher resting RSA was
associated with larger ERN ampUtude for the highest working memory load condition. This
finding suggests that those individuals with greater autonomic regulatory control exhibited
more robust ACC error-related responses on the most challenging task condition. On the
other hand, exploratory analyses with rate pressure product (RPP), a measure of sympathetic
arousal, indicated that higher pre-test RPP (i.e., more sympathetic influence) was associated
with more errors on "catch" NoGo trials, i.e., NoGo trials that simultaneously followed other
NoGo trials, and consequently, reqviired enhanced response control. Higher pre-test RPP was
also associated with smaller amplitude ERNs for all three working memory loads and smaller
ampUtude P3s for the low and medium working memory load conditions. Thus, higher pretest
sympathetic arousal was associated with poorer performance on more demanding "catch"
NoGo trials and less robust ACC-related electrocortical responses.
The findings firom the present study highlight tiie interdependence of electrocortical
and cardiovascular processes. While higher pre-test parasympathetic control seemed to relate
to more robust ACC error-related responses, higher pre-test sympathetic arousal resulted in
poorer inhibitory control performance and smaller ACC-generated electrocortical responses.
Furthermore, these results provide a base from which to explore the relation between ACC
and neuro/cardiac responses in older adults who may display greater variance due to the
vulnerabihty of these systems to the normal aging process.